Ship project history: Design of
"O" class submarines was developed on the basis of "L" class boats. New ships intended for service in the Far East
and so they required increased endurance and improved
seaworthiness in comparison with prototype. Lead Oberon
had saddle-tank construction and was built under the 1923 program, operational diving depth
was 60 m, maximal was 155 m. Oil fuel tanks were out of a pressure hull and were
leaked at big depth. It was possible to be saved of this lack during repair, when
riveted tanks were been replaced by welded (also fuel stowage has increased to 186t). Designed speed
was 15/9kts, but it has not been even reached. Oberon became the first
British submarine with sonar provided even at designing.